Why it happens

NRDS most often occurs when there isn't enough surfactant in the lungs. This substance, made up of proteins and fats, helps keep the lungs inflated and prevents parts of the lung called air sacs collapsing.

Problems with the genes can play a role in lung development, but this is very rare.

It's estimated half of all babies born before 28 weeks of pregnancy will develop NRDS. However, this has reduced in recent years, as steroid injections can be given to mothers at risk of NRDS during premature labour.

Signs and symptoms

The signs of NRDS are often noticeable immediately after birth and get worse over the following few days.

They can include:

blue-coloured lips, fingers and toes

rapid, shallow breathing

flaring nostrils

a grunting sound when breathing

As premature babies are usually born in hospital, most babies with NRDS are already in hospital when they develop these problems and receive treatment.

If you give birth outside hospital and notice the above symptoms in your child, call 999 immediately and ask for an ambulance.

Diagnosing NRDS

A number of tests can be used to look for the signs of NRDS and rule out other possible causes.

These tests may include:

a physical examination

blood tests – to measure the amount of oxygen in the blood and check for an infection

a pulse oximetry test – to measure how much oxygen is being absorbed in the blood, using a sensor attached to the fingertip, ear or toe

Complications

In the majority of cases NRDS can be treated successfully, and deaths directly linked to NRDS are rare in the UK.

However, in more severe cases there's a risk of further problems. These can include scarring to the lungs, leading to longer-term breathing problems. There's also a risk of brain damage, which may result in problems such as learning difficulties.